1. Field of the Invention
The present invention relates to a needle threader for inserting a thread into an eye of a sewing needle.
2. Description of the Related Art
In general, it is difficult, particularly for a weak-sighted person, to thread a needle. To facilitate a needle threading operation, a device called "needle threader" is commercially available.
FIGS. 14 through 16 of the accompanying drawings show a typical prior art needle threader. As shown in these figures, the needle threader denoted by a reference sign "B" comprises a synthetic resin body 80, a needle holder 81 extending vertically on the body 80 for receiving a needle 9, a needle pusher 83 located at one side of the needle holder 81, and a thread positioning portion 84 provided between the needle holder 81 and the needle pusher 83 for placing a thread T. The needle holder 81 has a needle receiving hole 81a and a thread inserting tunnel 81b intersecting the needle receiving hole 81a. The needle pusher 83 is reciprocally movable into and out of the thread inserting tunnel 81b (as shown by an arrow Na) for inserting the thread T into the eye 90 of the needle 9.
Specifically, as shown in FIG. 14, the needle 9 is positioned in the needle receiving hole 81a with its eye 90 directed below, and the thread T is placed between the needle holder 81 and the thread pusher 83. Then, the thread pusher 83 is moved forward to push the thread T, as bent, into the thread inserting tunnel 81b, thereby causing the thread T to be inserted into the needle eye 90. When the tip of the thread pusher 83 passes beyond the thread inserting tunnel 81b, a part of the thread T also projects out of the thread inserting tunnel 81b, as shown in FIG. 15. In this condition, the user nips the projecting part of the thread T for pulling while the thread pusher 83 is allowed to move backward, as shown by solid lines in FIG. 16. Finally, the needle 9 is lifted up out of the needle holder 9 together with the inserted thread T, as shown by broken lines in FIG. 16.
While the prior art needle threader greatly facilitates needle threading in comparison with an entirely manual operation, it still has the following problems.
For ensuring smooth and reliable insertion of the thread T into the needle eye 90, the needle 9 must be accommodated in the needle receiving hole 81a accurately so that the needle eye 90 is aligned exactly with the thread inserting tunnel 81b. For this purpose, the cross section of the needle receiving hole 81a of the needle holder 81 varies gradually from a circular shape to an oval shape for suitably orienting the needle 9 which has a similarly varying cross section. However, since the needle receiving hole 81a needs to be slightly larger in cross-sectional size than the needle 9, the needle 9 may rotate slightly about its own axis within the needle receiving hole 81a, so that the orientation of the needle eye 90 may deviate or offset slightly from the exact orientation. As a result, the thread pusher 83 may fail to properly insert the thread T into the needle eye 90. Particularly, since the thread pusher 83 must pass the needle eye 90 together with the bent thread T, even a slight offset often obstructs needle threading. Further, the thread pusher 83 may be damaged by such a movement obstruction if the user forces the thread pusher 83 forward.